TDOA/GPS hybrid wireless location system

Abstract

A method and system for enhancing the accuracy and robustness of locations determined for a mobile wireless transceiver in a cellular telephone communications system integrates location-related information both from an assisted GPS device embedded in the mobile unit and from infrastructure-based facilities that extract signal characteristic data at networked base stations. Available supporting collateral information may be additionally evaluated in the location determinations to provide location estimates of enhanced robustness and accuracy.

Description

FIELD OF THE INVENTION [0001] The present invention relates generally to wireless location systems, and more particularly to a wireless location system that employs both infrastructure-based and handset-based approaches for locating wireless devices. Some of the exemplary aspects of the present invention are particularly suited to a wireless location system and related methods and subsystems compatible with the Global System for Mobile Communication, or GSM. It should be noted, however, that although aspects of the systems and methods described herein relate specifically to a GSM system, the claims at the end of this specification are not to be construed as limited to a GSM system, except as they may be explicitly so limited. BACKGROUND OF THE INVENTION [0002] The present invention relates to the determination of the location of a mobile radio-frequency transceiver operating within the operational domain of a wireless communications network. In particular, the mobile units of primar...

AI Technical Summary

Benefits of technology

"The present invention provides a technology for integrating information from both GPS-based and infrastructure-based processing to locate wireless mobile communication units. The invention allows for the efficient use of both types of data to improve accuracy and reliability in location determination. The invention also provides assistance data to the mobile unit to help it extract location-related information from GPS signals. The location-related data can include time of arrival, time difference of arrival, angle of arrival, signal strength or propagation loss, and timing advance. The invention also takes into account collateral information and meets applicable accuracy requirements for E-911."

Problems solved by technology

To date, the system architectures implemented for the diverse localization approaches have not readily supported the information integration needs.

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